You can calculate it pretty easy on OSH Park. $5 per square inch for a set of three. So it'd be $1760 / 3 or about $587 per, plus shipping. Though Seeed Fusion would be MUCH cheaper in this case if you were willing to settle for metric 50 cm max.. $326 for 5 pieces (plus color fee... $10-20 and shipping). About $65 per panel.Making PCBs really is not expensive these days.. even full sized panels.

I've been painting, and etching boards for decades. I'm annoyed I didnt think of this but Kudos to you and David for actually doing it, also for allowing OSHPark to handle the production to their Royal Purple standard :-)